This lets us avoid generating SWZ instructions. Those instructions could
be constant folded but that complicates the replication analysis
introduced in the next commit.
Almost no shader-db changes.
quadwords HURT: shaders/glmark/1-22.shader_test MESA_SHADER_FRAGMENT: 718 -> 722 (0.56%)
total quadwords in shared programs: 68169 -> 68173 (<.01%)
quadwords in affected programs: 718 -> 722 (0.56%)
helped: 0
HURT: 1
Signed-off-by: Alyssa Rosenzweig <alyssa@collabora.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/14576>